Electrolytic cell.



UNITED STATES PATENT OFFICE.

ROBERT GRISSON, OF HAMBURG, GERMANY.

ELECTROLYTl C CELL.

SPECIFICATION forming part of Letters Patent No. 719,791, dated February3, 1903.

Application filed December 8, 1902. Serial No. 134,356. (No model.)

To all whom it may concern.-

Be it known that 1, ROBERT GRISSON, a subject of the German Emperor, anda resident of Hamburg, in the German Empire, have invented certain newand useful Improvements in Electrolytic Cells, of which the following isa specification.

The present invention relates to improvements in electrolytic cellsespecially of that class provided with an electrode or electrodes ofaluminium or an equivalent material. The object of the invention is toproduce an improved electrolytic cell of the class mentioned in which areformation of the deformed aluminium electrode or electrodes isconstantly proceeding during the operation; and

with this end in View my invention consists.

in certain novel features of construction and arrangements of parts, aswill be hereinafter fully described with reference to the accompanyingsheet of drawings, in which-- Figure l is a vertical section of anelectrolytic cell having one aluminium electrode and one lead electrodeconstructed and arranged in accordance with and embodying my invention.Fig. 2 is a vertical section of a modification of the electrolytic cellprovided with two aluminium electrodes.

Similar letters refer to similar parts throughout both figures.

Experience has shown that cells with aluminium electrodes as hithertoconstructed have not attained any practical importance, because whenthey have been in use for a short time they afford a passage to thealternating current in both directions. Owing to the electrolytic actionof the current, small holes are quickly formed in the electrodesvertically suspended in the electrolyte, and in working these increasein size, so that there is no longer an insulating stratum. As thesedefects increase so does the loss of energy, which may directly balanceitself between the electrodes. It was therefore necessary to producea'cell in which a reformation of the deformed aluminium electrode orelectrodes is constantly proceeding during the operation. This result isattained by avoiding any vertical active surfaces in the aluminiumelectrode. As a formation of aluminium with alternating current onlytakes place with a weak current, a constant formation of the activesurfaces during the operation or working of the cell is obtained, owingto the fact that upon those points of the electrode at which a passageof current takes place a gas-bubble is formed, which, if there are novertical surfaces, cannot immediately escape, and thus prevents thepassage of a strong current at this deformed point and permits of areformation. The bubble escapes after the reformation slowly to one sideor edge of the electrode and the process is repeated. It may be statedthat the active surface of the aluminium electrode may not lieabsolutely horizontal. It may be slightly inclined or be of the form ofa spherical cap. The electrode must be formed in such a manner that thegas-bubbles produced reduce the passage of current at the deformedpoints to such an extent as to permit of reformation there.

The improved electrolytic cell with a horizont-al or onlyslightly-inclined aluminium electrode orelectrodes produces, as statedby careful experiments, a far better result, as the well-knownelectrolytic cells with a vertical aluminium electrode or electrodes.

The improved electrolytic cell may advantageously be employed or used asa rectifying-cell for transforming alternating currents into direct orcontinuous currents, as a looking or barringcell in chargingaccumulators, as an alternating-current condenser, &c.

In the electrolytic transforming-cell shown by Fig. '1 01. represents asuitable jar or cup containing a suitable electrolyte 1), into which areimmersed an aluminium electrode 0 and an electrode d of lead or anyother suitable material. The plate 0, forming the aluminium electrode,is arranged in such a manner that vertical active faces are entirely ornearly entirely obviated. c and d are conducting wires or strips leadingto and carrying or supporting the said electrodes 0 and d, respectively.In order to prevent direct contact between the electrolyte and theconducting-strips c d, the latter are surrounded or I inclosed insuitable insulators c and d respectively, made of glass or any othersuitable insulating material. When the electrode c is connected with thepositive pole of a generator, current cannot pass, as is well known,from c to d; but should the current be reversed it may pass from d to c.

In the modified form of the improved cell represented by Fig. 2 twohorizontally-arranged aluminium electrodes 0 are shown in the jar acontaining a suitable electrolyte b. In this case current can pass,as iswell known, in neither direction. The cell forms an electrolyticcondensing-cell or condenser.

Having fully described myinvention, what I claim, and desire to secureby Letters Patent, is-

1. In a transforming or condensing cell, electrodes therein, and asuitable electrolyte, one of said electrodes of aluminium and havingsubstantially no vertically-disposed active surfaces, for the purposeset forth.

2. In a transforming or condensing cell, electrodes therein, and asuitable electrolyte, one of said electrodes of aluminium and positionedto prevent the immediate escape of gas-bubbles formed on its surface,whereby the electrode is corroded and at such points a gas bubble orbubbles formed, thereby reducing the current thereunder sufficiently toenable a redeposit of aluminium, substantially as and for the purposeset forth.

3. In a transforming or condensing cell, aluminium electrodes therein,and a suitable electrolyte, both of said electrodes presenting surfacesto the electrolyte that do not readily release gas-bubbles formedtherein, whereby the electrode is corroded and at such points a gasbubble or bubbles are formed, thereby reducing the current thereundersufficiently to enable a redeposit of aluminium, substantially as andfor the purpose set forth.

ROBERT GRISSON.

Witnesses:

MAX KAEMPFF, OTTO W. HELLMRIOH.

